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You dont hear so much these days about good old-fashioned tornados, the kind that took Dorothy out of Kansas and deposited her in Oz. Hurricanes sweeping in off the Atlantic or Caribbean get all the press. But, twisters havent gone away. In fact, they still terrorize Kansas. Just ask the folks in Greensburg.

When an F5 class tornado roared through earlier this summer, it all but flattened the town of about 1,500 in the southwest part of the state. Images available on the Web are truly horrific; it looks like a nuclear blast site. Luckily, the residents had about 30 minutes warning and casualties were limited.

The recovery process began almost immediately, with Xirrus Inc., a Wi-Fi WLAN equipment provider on the scene to help the Greensburg School District get its temporary school site online. 95 percent of the buildings in the town were leveled by the tornado, including the elementary and high schools, yet school opened on time in late August.

Xirrus, which makes multi-radio Wi-Fi network arrays that it claims out perform conventional networks using single-radio access points, donated labor and consulting, and gave the school district a healthy discount on equipment, says Jon Freeman, the companys director of sales and marketing for the Central U.S.

The first time I went out there, it was just rubble, Freeman says of the devastation. All you could see were lines of red dump trucks going in and out of the town--there must have been 100--and heavy equipment everywhere.

They were depositing all the rubble in a dump and burning it. So there were these black clouds of smoke rising over the town. It was the most horrible thing youve ever seen. Greensburg used to be known as a town of trees, but all their branches were ripped off. It looked like something out of a Tim Burton movie.

It took two of the four-radio Xirrus XS-3500 Wi-Fi arrays--about $750 per radio--to cover the temporary school. The site is a flat open space with two groups of portable classrooms, one for elementary, one for high school, clustered around a shared gymnasium. Of the 290 students registered last year, 270 showed up for the first day this year.

Freeman and a helper from a nearby university mounted the devices atop recycled telephone poles planted at the site for the purpose. The arrays are enclosed in Xirrus XE-4000 outdoor enclosures--a necessary precaution since it gets a little windy in Greensburg in the summer sometimes, and cold and snowy in winter. Construction workers hoisted them up with a cherry picker. AT&T looked after all the wiring.

The whole install took maybe four hours, Freeman says.

The essential value proposition for the Xirrus technology is that it provides more bandwidth, greater range, and lower cost, mainly because its easier to implement since there are fewer devices and less wiring. In fact, as nice as the feel-good Greensburg disaster relief story is, the companys own story is pretty interesting too.

The arrays have it

Xirrus was formed in 2003 by CEO Dirk Gates, CFO Steven DeGennaro, and chief development officer Patrick Parker, who met at Xircom Inc., the mobile networking products company acquired by Intel in 2001. Xirrus was in stealth mode for two years while developers came up with the ideafor the architecture, which they basically stole from cellular technology.

The idea is simple. Instead of a single-radio access point using one Wi-Fi channel and creating a bubble of coverage around it, the Xirrus arrays package a number of radios--four, eight, or 16, a mix of 11b/g and 11a--arranged in a circular formation, each using one channel and each with its own high-gain directional antenna that provides a carefully delimited pie slice of coverage.

Xirrus has patents on much of this technology, including the directional antenna arrays, as well as a feature it refers to as, Sharp Cell, which ensures even distribution of signals in overlapping multi-array deployments, and recent new technology that allows remote rebooting of arrays to make managing networks easier.

The largest of the Xirrus arrays delivers 864 Mbps of bandwidth, or up to eight times the capacity of single-radio APs used in conventional Wi-Fi deployments. Each array has its own controller built in, which orchestrates packet delivery, changes channels on the fly as conditions dictate, and coordinates security and quality of service (QoS) functions for all of the integrated APs. The arrays work with any Wi-Fi client device.

Xirrus says its solution also delivers twice the range, four times the coverage and 14 times the throughput, while requiring 75 percent less in the way of devices, cabling, and switch ports (the arrays use just one switch port for multiple APs, whereas conventional single-radio APs each use a port).The reduction in physical infrastructure helps reduce installation time.

Freeman says these claims have all been corroborated by The Tolly Group, a supposedly independent and unbiased network equipment testing company. Xirrus commissioned The Tolly Group to run its products through their paces. Of course, the comparison is being made between a multi-radio device and a single-radio AP, so in some ways its a little unfair.

The bottom line, though, is that Xirrus delivers better price performance. Freeman says it typically comes in with estimates for fully installed networks that are 40% below competitors, sometimes as much as 80 percent below. There is a huge economy-of-scale benefit to integrating all that RF complexity in one box, he says.

The company doesnt claim any further total-cost-of-ownership advantage over competitors, but Freeman says some customers have pointed out that fewer devices also mean easier maintenance and management. They believe there is an additional operational savings over time.

Playing catch-up

So why isnt everybody buying Xirrus?

The company began marketing the Wi-Fi array products in early 2005. Xirrus was two years behind competitors in bringing an enterprise-grade Wi-Fi solution to market, Freeman points out--but were rapidly making up [for lost time].To date, it says it has sold over 10,000 units.

He points to the number of reference customers that agree to appear at the Xirrus Web site as evidence of the traction the company is gaining in the market--way more than competitors post at their sites, he claims. More to the point, the company has been almost doubling revenues on a month-over-month basis recently.

When [prospects] find out about our technology, we rarely run into a situation where we dont cream the competition, Freeman boasts. Were winning hand-over-fist against all of our competitors--even the 800-pound gorilla. (He means Cisco.)

Xirrus is mainly targeting schools, colleges, hospitals, and hotel chains. To a large extent thats just reactive to where the market is, Freeman says. About the only kind of business it wont go after is municipal Wi-Fi, which the company believes will ultimately not work.

Is Xirrus set to wreak havoc in the Wi-Fi industry? If the technology is as good as the company says, and if it can prove it--which it increasingly can, with glowing reviews from customers--it might very well blow away a few of its smaller rivals.

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